In currently available tractors, because of the limited availability of space within the cabin and around the dashboard, some equipment is frequently mounted overhead. Aside from an interior light, one may find speakers, a heater blower or exterior spotlights mounted on the cabin roof. For ease of manufacture, the roof and all the equipment mounted on it are pre-assembled and offered up as a completed roof assembly to the cabin frame. The outer part of the roof is usually made as a plastics moulding and for insulation as well as styling a headliner may be secured to the inside of the outer part as part of the roof assembly.
Existing roofs are designed to be aesthetically pleasing and to provide weather protection but they have not needed to be designed for strength or robustness. This is because the roof assembly is secured to a rigid cabin frame which itself has sufficient structural strength to protect the driver.
However, EEC health and safety regulations require all construction plant to have Falling Object Protective Structures (FOPS). To comply with EEC regulations, a tractor roof must now offer the driver protection against falling objects and current roof assemblies fail to meet this requirement.
The aim of the present invention is to provide a roof structure for the cabin of a tractor that can still benefit from the advantages afforded by pre-assembly yet sufficiently robust to act as a falling object protective structure complying with health and safety regulations.